Hach Polymetron 2582sc Manual Del Usuario página 25

Problem
The measurement is
not accurate.
The sensor current is
0 mA during
measurement.
The sensor current is
negative.
The sample
temperature is not
within specification.
The measurement
shown on the display
is not numeric.
Probable cause
The permeability of the
membrane has changed (dirt
deposits).
There is contamination in the
electrolyte.
There is an electrolyte leak.
There are interferences with the
measurement (primarily with
H S).
2
An error occurred during
calibration or the calibration is
incorrect.
There are air bubbles near the
cathode.
The sample flow rate too low
(4 mL/h minimum).
The sample temperature or
sample pressure is not within the
instrument specifications.
There is sludge or particles on
the cathode.
There is no electrolyte in the
sensor (leak).
The sensor cable is disconnected
or not fully connected.
There is a connection problem to
the anode circuit (loose contact).
There is a dark green deposit of
silver bromide (AgBr) on the
surface of the silver anode of the
electrode.
There may be a short-circuit on
the temperature connection.
The measured value is less than
0 ppb if negative signs are
displayed.
The measured value is more than
10,000 ppb.
The sensor is in standby mode,
because the measured value is >
2 ppm.
Resolution
Calibrate the sensor. Identify if the concentration
measurement is back to normal.
Examine the screw-in parts (membrane, filling
screw, filling washer). Replace the electrolyte and
membrane.
Examine the screw-in parts (membrane, filling
screw, filling washer). Replace the electrolyte and
membrane.
If the level of H S (or other contaminate) is stable,
2
adjust the dissolved oxygen measurement by the
concentration of the contaminate.
Calibrate the sensor again to examine the
parameters. If the error continues, examine the
calibration current (too high, too low or unstable) and
the concentration in air. Refer to the previous
problems in this table.
Refill with electrolyte. Make sure that there are no air
bubbles at the bottom of the sensor body.
Increase the sample flow rate.
Change the sensor location or adjust the sample so
that it is within specifications.
Clean the cathode with a soft and absorbent tissue.
Replace the membrane.
Examine the screw-in parts (membrane, filling
screw, filling washer). Replace the electrolyte.
Examine the sensor cable connections at the
module in the controller and at the sensor.
Examine the sensor cable connections at the
module in the controller and at the sensor.
Do the steps in Replace the membrane
and Clean the electrode
Examine the sensor cable connections at the
module in the controller and at the sensor.
Do a zero calibration.
Replace the controller.
Do the steps in Exit standby mode
on page 21
on page 22.
on page 16.
English 25